Device for opening paper cartons



April 24, 1951 J. J. GREGG 2,550,346

DEVICE FOR OPENING PAPER CARTONS Filed May 12, 1950 FIC3.I

INVEN'TQR JOSEPH J. GREGG A TORNEYS normal condition; and

Patented Apr. 24, 1951 UNITED STATES PATENT OFFICE DEVICE FOR OPENING PAPER CARTONS Joseph v J. Gregg, Springfield, Mass. Application May '12, 1950, Serial No. 161,626

2Claims. (Cl.30-2) when not being used and is quickly and easily convertible to a condition of utility.

I Another object of the invention is to provide a cutting instrument of simple and sturdy'construction with a minimum of parts, for economy in manufacture and a long useful life.

These and other objects and advantages of the invention will be understood from the follow- ,ing description in connection with the accompanying drawings, in which:

Fig. 1 is a perspective view showing the new cutter device as used to opena carton;

Fig. 2 is a view with the casing of the device broken away to show the relationship of parts in Fig.3 is a view similar to Fig. 2 to show operative position of the parts.

As shown by Fig. l, the new device is adapted to be positioned upon a corner edge portion 2 of a generally rectangular paper board carton 3 or the like, and then to be drawn along said edge to make a cut or incision, such as is indicated at 4, in a wall margin of the carton immediately adjacent and parallel to the carton edge. The instrument may be drawn along three adjacent edges to provide a hinged cover for the carton, or it may be used to cut four adjacent edges if a hinged cover is not desired for the carton.

The cutting device includes a substantially rec tangular frame 5 with a cutting knife blade 6 held slidably therein. A flanged extension I is provided along one edge of the frame 5. The.

inner surface of the extension 1 forms, with the adjacent frame edge 8, a pair of right-angled surfaces for slidable engagement with a pair of adjoining carton walls along the carton edge.

A slotted opening 9 is positioned near one end of 7 slidingly reciprocated through the slotted opening 9.

, A recessed cavity I2 is provided in the frameadjacent the slotted opening 9 to intersect the lower end of the diagonal recess formed by shallow walls II. The upper end of cavity I2 is 're+ duced to an angular slit as at I3. In the slit a curved leaf spring I4 is anchored. The spring is arched in the cavity I2 and is yieldingly pressed against the lower end edge of the knife blade 6. As shown by the drawings, the bias of spring I4 normally serves to force the blade 6 upwardly away from the slotted opening 9 and to project into an enlarged recess I5, which is in longitudinal alignment withthe diagonal recess. The recess I5 is shouldered inwardly as at IE to provide a pair of abutments to secure a slidable finger piece H in the recess. The narrowed outer end of recess [5 intersects the peripheral edge of the frame 5. V

The finger piece I8 with outwardly offset portions I9 on enlarge; ments at the extremities thereof, the portions I9 engaging the abutments at I6 to limit outward movement of the finger piece when pressed by the spring I4. The inner ends of prongs It} en- J Y gage the upper end edge of the knife blade 6 when the finger piece is pressed inwardly against the spring to project the bladethrough slot 9 (Fig. 3) the movement of piece I! is limited by an abutment 20 formed by the inner end of recess I5.

It will be noted the rectangular frame 5 is formed with two pieces, 'a body portion 2I in which the recessed portions are formed and a.

cover plate portion 22 overlying the recessed surface of portion 2 I The body portion 2| is stepped as at 23 diagonally across the upper corner thereof in line with the abutment walls 20 of recess I5.

The cover member 22 has a mating stepped portion to fit in position over the face of the body and is fixed by suitable means as by plastic cementing to cover and hold the spring I4 and blade Ii in position in the frame. This interfitting relation of stepped portions facilitates the assembly of the cover 22 of the frame on the body 2| in the attachment of the two portions.

It will be readily appreciated that spring I4- normally holds the knife 6 away from opening 9, so that said knife does not protrude beyond the frame edge 9. Fig. 2. In use, the finger piece I! is depressed to project the lower corner of the knife blade beyond frame edge 8, for cutting action. This is shown by Fig. 3.

Preferably the knife 6 consists of a discarded razorblade. It will be understood that any generally rectangular blade may be used in the g The example shown by the accompanydevice.

I I includes a pair of prongs" This condition is illustrated by plastic material.

ing drawings has been proportioned to accommodate a blade, well-known as a Shick injector blade. The recess of frame 5 may, however, be formed to accommodate other types of blades as desired.

The frame and finger piece is preferably of The prongs of finger piece I! have sufiicient resiliency so that the ends thereof can be momentarily compressed for insertion and removal through the narrowed outer walled passage of recess [5.

The device may, of course, be manipulated. in any manner convenient to or desired by the user.

Fig. 1 illustrates one way of handling the carton,

opener as by depressing the piece I! with the 4 ing, an enlarged recessed extension of said blade recess remote from said cavity and intersecting the peripheral edge of said frame, a finger piece reciprocably held in said recessed extension and engaged against the adjacent end edge of said blade, and means to limit themovement of said finger piece outwardly of its recessed extension, the inner end of said extension forming an abutment for limiting inward movement of said finger piece.

2. A device for opening paper cartons and the like comprising a frame having along one edge a flanged extension, the inner surface thereof index finger and pushing the opener to'cut the upper surface of a carton top. It will be realized that it may be perhaps equally or more convenient to hold the device with the piece I! placed.

against the thumb pad of the users hand, with the index finger curled around the top edge of the frame 5 and the tip of the finger pressed against the frame side edge opposite the piece H. In this case the-device will be drawn along the carton edge with the extension I resting on the top edge of the carton so as to make the incision along the side thereof.

What is claimed is:

1. A device for opening paper cartons and the like comprising a unitary frame having along one edge a flanged extension, the inner surface thereof forming with the adjacent frame edge a pair of right angled surfaces for slidable engagement along adjoining carton walls, a slotted opening in said adjacent frame edge near one end of the same, a recess in the body of said frame, said recess communicating with said slotted opening, a knife blade in said-recess adapted to be slidably reciprocated through said slotted opening, a recessed cavity in the frame adjacent the slotted opening and intersecting the recess, a spring anchored in the cavity engaging one end edge of said knife blade, said spring normally urging said knife blade away from the slotted opening and being movable in the cavity to permit extension of a corner of the blade through said openforming with the adjacent frame edge a pair of right angled surfaces for slidable engagement along adjoining carton walls, a slotted opening in said adjacent frame edge near one end of the same,'an elongated recess having parallel longitudinal walls disposed diagonally in the body of said frame, said recess communicating at one end with said slotted opening, a knife blade slidably held by the Walls of said recess, a recessed cavity in the frame adjacent the slotted opening and intersecting the diagonal recess, a spring member anchored in the cavity engaging an end edge of said knife blade, said member normally urging said knife blade away from the slotted opening and being movable in the cavity to permit extension of a corner of the blade through said opening, an enlarged recess in longitudinal alignment with the other end of said elongated recess and intersecting the peripheral edge of said frame, a finger piece slidably mounted in said enlarged recess and provided with spaced prongs at the inner endthereof, the end extremities of said. prongs being engaged against the adjacent end edge of said bladeand having outwardly offset portions, said enlarged recess having inwardly shouldered portions forming an abutment engageable by said offsets to limit movement of the finger piece outwardly ofsaid recess, the inner end of said recess forming an abutment for limiting inward movementof said finger piece.

'JOSEPH J GREGG. 

